1. Field of the Invention
This invention relates generally to swimming pools and more particularly to a new and improved water circulation system for filtering the water and automatically cleaning the interior surfaces of the swimming pool.
2. Description of the Prior Art
Various automatic cleaning systems and devices have been successfully used to eliminate or at least substantially reduce the tedious and repetitious task of manually cleaning dirt, sediment, leaves and other foreign matter from the bottom and sidewalls of swimming pools.
Among the cleaning devices in common use, are those usually referred to as "whips". Elongated flexible tubes are connected to suitable fixtures provided at various locations in the sidewalls of the swimming pool. Water under pressure is directed to the tubes causing them to whip, that is, move in a sinusoidal motion, in response to jet efflux from the ends of the tubes. The whipping action and jet streams agitates settled foreign matter and places it in suspension so that it can be carried through the swimming pool's water circulation system and extracted from the water by the inherent action of the filtering system.
Another cleaning system and device accomplishes the same objective by providing a plurality of motor driven rotating jet nozzles located at various locations in the bottom of the pool. These jet nozzle devices are rotatably driven and the jet streams efflux from the nozzles is a result of the water under pressure which is supplied thereto.
A third, and probably most commonly used type of pool cleaning device is generally referred to as a "pool sweep". Although there are several types of pool sweeps available, they all operate more or less on the same basic principles. Pool sweeps are usually hydro-mechanical mechanisms which are teathered by a single elongated flexible hose to a suitable water supply conduit which terminates in a pool sidewall mounted fitting. The hose directs water under pressure to the pool sweep to drive it in random movement paths about the interior of the pool and to operate the agitation device or devices of the pool sweep.
As is well known, a swimming pool water circulation system must be operated at relatively low pressure high volume flow rates for proper and efficient water filtration. As a result of this, a problem exists in that all of the pool cleaning systems or devices discussed above require that the water supplied thereto be at a relatively high pressure low volume flow rate for proper and efficient operation.
U.S. Pat. No. 3,483,878 suggests that this problem can be overcome by diverting some of the low pressure high volume water flowing through the circulation system, restrict the volume of the diverted water by use of a manually adjustable gate valve to increase its pressure and supply the diverted water to a cleaning system. Therefore, in this prior art system water will flow back to the pool through the usual return plumbing arrangement and will be simultaneously supplied to the cleaning system. However, this prior art system results in a compromise in that an unsatisfactory reduction of the water flow rate in the circulation system results in a loss of filtration efficiency and the diverted water supplied to the cleaning device is at a less than ideal high pressure low volume flow rate required for efficient operation of the cleaning device.
For this reason, it is a common prior art practice to install a booster pump in a reduced diameter water diversion conduit leading from the pool's water circulation system to the cleaning device or devices. Such a booster pump provides the needed high pressure low volume water flow to the cleaning device or devices without reducing the low pressure high volume flow rate in the filtering system.
However, the addition of a booster pump causes problems in that it, of course, increases the initial and operating costs, increases the complexity of the water circulation system, and increases the possibility of system failure or malfunction.
Therefore, it is desirable to provide a new and improved swimming pool water circulation system which overcomes, or at least substantially reduces, the problems of the prior art.